Generally, separating screens are fitted into shaker baskets, with each shaker basket having a plurality of screens. It is therefore necessary to provide a seal where adjacent screens abut and also where screens abut the shaker basket. It is known to co-mould a seal onto the edge of a screen body and also to attach a seal to a screen body by adhesives or by the use of fasteners such as screws. There are disadvantages associated with these known techniques and the invention aims to provide a different way of providing a seal on a screen body.